http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Turbulent mixing and deposition studies for single point aerosol sampling
xviii, 159 leaves : illustrations ; 28 cm.
A generic mixing system has been developed which creates suitable conditions for single point stack sampling of effluent air emission points. Results show that the system performance is well within the EPA mixing criteria - the COVs for velocity tracer gas concentration and 10 []m AD aerosol particles are less than half of the EPA permissible level of 20%. Experiments were conducted to characterize the degree of mixing at downstream locations as affected by several types of flow disturbances, including 900 elbows and commercial static mixing devices. It was found that the mixing is impacted by the upstream flow turbulence and that the use of static mixing elements can greatly enhance the mixing process. A stack system has been characterized which creates conditions suitable for single point representative sampling. The stack system could be used in both existing and new stack or duct configurations. It could also be used as an aerosol wind tunnel for testing various sampling devices. Results show that the system performance is well within the EPA permissible limits. A mixing model has been developed which can predict mixing of tracer gas in turbulent air flows in piping systems comprised of a series of 90° elbows. The model uses the concept of an equivalent length of straight pipe that would produce the same degree of mixing as the mixing element under consideration. There is good agreement between experimental and predicted results. Aerosol penetration thorough flow splitters was experimentally and numerically investigated. A surface plot was generated from the experimental data to predict aerosol penetration as a function of the Stokes number and the bifurcation angle between the two outlets of the splitters. The developed correlation is valid in the ranges of 0.034 < Stk < 1.248, 2,556 < Re < 13,630, and 30° < [] < 180°, and should be a useful sub-model for predicting aerosol particle losses in flow splitters in software programs, e.g., DEPOSITION. Numerical studies were conducted with a commercial computational fluid dynamics (CFD) software, FLUENT, and a Lagrangian particle tracking code. Good agreement was found between the experimental and numerical results.
"Major Subject: Mechanical Engineering".
Issued also on microfiche from University Microfilm Inc.
Includes bibliographical references (leaves 150-158).